diff --git a/core/modules/datetime/src/Plugin/Field/FieldType/DateRangeFieldItemList.php b/core/modules/datetime/src/Plugin/Field/FieldType/DateRangeFieldItemList.php
index f04efb1..3ff6a6c 100644
--- a/core/modules/datetime/src/Plugin/Field/FieldType/DateRangeFieldItemList.php
+++ b/core/modules/datetime/src/Plugin/Field/FieldType/DateRangeFieldItemList.php
@@ -95,7 +95,8 @@ public static function processDefaultValue($default_value, FieldableEntityInterf
     // Explicitly call the base class so tht we can get the default value types.
     $default_value = FieldItemList::processDefaultValue($default_value, $entity, $definition);
 
-    // Allow either the start or end date to have a default, but not the other.
+    // Allow either the start or end date to have a default, but not require
+    // defaults for both.
     if (!empty($default_value[0]['default_date_type']) || !empty($default_value[0]['default_end_date_type'])) {
       // A default value should be in the format and timezone used for date
       // storage. All-day ranges are stored the same as date+time ranges.  We